Mario Cirillo

The development of cognitive impairment (CI) is a frequent and debilitating consequence of COVID-19 and can persist for more than 1 year after the acute infection stage. Previous neuroimaging studies in COVID-19 survivors with CI have revealed widespread alterations in functional connectivity (FC), particularly within fronto-parietal circuits and subcortical nuclei such as the hippocampus, basal ganglia, and thalamus. This study focuses on neural correlates of CI in subjects who recovered from COVID-19 and the relationship between FC patterns and discrete cognitive domains. Resting-state functional MRI data from 136 subjects were analyzed using a ROI-to-ROI approach across 246 brain regions derived from the Human Brainnetome Atlas. Group comparisons were performed based on the presence or absence of CI, and correlation analyses were conducted between FC and scores obtained from a comprehensive neuropsychological test battery. Whole-brain FC showed no difference between patients with and without CI. In the whole study sample, hypoconnectivity between two basal ganglia regions and two frontal motor regions was associated with impaired performance in the cognitive domain “Reasoning and Problem-Solving,” while hyperconnectivity between the prefrontal thalamus and the postcentral gyrus was associated with impaired performance in the same cognitive domain. Our findings indicate that FC alterations within the cortico-striatal and thalamo-cortical circuits may subtend deficits in higher-order executive functions in post-COVID-19 patients and highlight the importance of examining discrete cognitive domains in relation to brain connectivity.

Background: Quantitative susceptibility mapping (QSM) is an advanced magnetic resonance imaging (MRI) technique that quantifies tissue magnetic susceptibility, offering non-invasive insights into brain microstructure, including iron content and myelination. While extensively applied in adult neuroimaging, its use in pediatric populations is rapidly expanding. Purpose: This systematic review aims to provide a comprehensive overview of QSM applications in pediatric brain imaging, highlighting methodological advancements, diagnostic potential, and current limitations. Methods: A systematic literature search was performed using PubMed and Google Scholar up to April 2025. Inclusion criteria were original research articles written in English, involving only pediatric populations (0–17 years) and employing QSM in brain imaging. Twenty studies met eligibility criteria and were analyzed in terms of acquisition protocols, post-processing methods, study objectives, and main findings. Results: A systematic search on PubMed and Google Scholar found 54 QSM brain studies in children; after exclusions, 20 original research papers qualified for review and were quality-checked using Quality Assessment of Diagnostic Accuracy Studies version-2 (QUADAS-2). Most studies were recent (85% in the last 5 years), in Asia (55%, with China 35%), and used 3-tesla (T) MRI (80%). Typical imaging parameters: 8 echoes (TE=40 ms), slice thickness=2–2.5 mm, matrix often 256×256; Laplacian was the main phase-unwrapping method and variable-kernel sophisticated harmonic artifact reduction for phase data (VSHARP) the dominant background-field removal. Study aims clustered into improved detection, microstructural analysis, normative comparisons, clinical correlations, developmental patterns, and pathology tracking. Conclusion: QSM emerges as a valuable tool in pediatric neuroimaging, offering quantitative biomarkers for brain development, disease monitoring, and potential clinical translation. Despite promising results, challenges remain, including motion artifacts, lack of normative pediatric data, and methodological heterogeneity. Future research should focus on longitudinal designs, standardization of protocols, and integration with complementary imaging modalities. With further refinement, QSM has the potential to become an integral component of pediatric neuroradiological assessment.

BACKGROUND: Brainstem cavernous malformations (BSCMs) are rare vascular lesions, most frequently located in the pons. Their surgical management is particularly demanding due to the dense concentration within the brainstem of eloquent neural pathways and nuclei. Among various surgical routes, the endoscopic endonasal transclival approach (EETA) has been established as a valuable option for treating selected ventrally located lesions. OBSERVATIONS: The authors report the case of a 54-year-old woman with a ventral pontine cavernous malformation (CM) presenting with recurrent hemorrhagic episodes, all resolving without neurological sequelae. Based on the anterior midline location of the lesion within the pons and the posterolateral displacement of the corticospinal tracts (CSTs) on preoperative tractography, an EETA was deemed the most suitable approach. Gross-total removal was achieved without neurological worsening or postoperative CSF leakage. LESSONS: This case supports the use of EETA as a safe and effective surgical route for ventral pontine CMs with anterior surface presentation. Accurate preoperative planning, including assessment of CST displacement via diffusion tensor imaging, and direct intraoperative cortical stimualtion are essential for identifying a safe entry point. Although technically demanding and not universally applicable, EETA offers a direct surgical corridor that minimizes neurovascular manipulation and facilitates favorable outcomes in selected cases. https://thejns.org/doi/10.3171/CASE25356

Background: Multiple genes can disrupt hypothalamic–pituitary axis development, causing multiple pituitary hormone deficiencies (MPHD). Despite advances in next-generation sequencing (NGS) identifying over 30 key genes, 85% of cases remain unsolved, indicating complex genotype–phenotype correlations and variable inheritance patterns. Objective: This study aimed to identify the MPHD genetics in three probands from two unrelated families. Methods: Family A had one affected child, while Family B had two affected siblings. All probands exhibited poor growth since birth, and family B’s probands were born small for gestational age. Growth hormone deficiency was confirmed in all subjects. Family B’s probands responded poorly to growth hormone treatment compared to the first patient. Furthermore, Family A’s proband and Family B’s younger sibling developed central hypothyroidism, while Family B’s older sibling presented hypogonadotropic hypogonadism. Brain magnetic resonance imaging (MRI) revealed pituitary hypoplasia, ectopic posterior pituitary gland, and small sella turcica in all probands. Patients and their available relatives underwent NGS. Results: NGS identified the same novel and likely pathogenic LHX4 variant (c.481C>G) in all probands despite the families being unrelated. Additionally, Family A’s proband carried a GLI2 variant (c.2105C>A), and Family B’s probands carried an IGF1R variant (c.166G>A), both interpreted as being of uncertain significance. Conclusions: This study confirms that heterozygous pathogenic variants of LHX4 can cause MPHD associated with a specific neuroradiological triad of abnormalities despite incomplete penetrance and variable phenotype. Moreover, the co-occurrence of the other two gene variants was debated. The IGF1R variant could explain the unusually poor response to growth hormone therapy in Family B, suggesting an oligogenic mechanism underlying the phenotype.

Background: Repetitive transcranial magnetic stimulation (rTMS) has shown therapeutic effects in neurological patients by inducing neural plasticity. In this pilot study, we analyzed the modifying effects of high-frequency (HF-)rTMS applied to the dorsolateral prefrontal cortex (DLPFC) of patients with mild cognitive impairment (MCI) using an advanced approach of functional connectome analysis based on network control theory (NCT). Methods: Using local-to-global functional parcellation, average and modal controllability (AC/MC) were estimated for DLPFC nodes of prefrontal-lateral control networks (R/LH_Cont_PFCl_3/4) from a resting-state fMRI series acquired at three time points (T0 = baseline, T1 = T0 + 4 weeks, T2 = T1 + 20 weeks) in MCI patients receiving regular daily sessions of 10 Hz HF-rTMS (n = 10, 68.00 ± 8.16 y, 4 males) or sham (n = 10, 63.80 ± 9.95 y, 5 males) stimulation, between T0 and T1. Longitudinal (group) effects on AC/MC were assessed with non-parametric statistics. Spearman correlations (ρ) of AC/MC vs. neuropsychological (RBANS) score %change (at T1, T2 vs. T0) were calculated. Results: AC median was reduced in MCI-rTMS, compared to the control group, for RH_Cont_PFCl_3/4 at T1 and T2 (vs. T0). In MCI-rTMS patients, for RH_Cont_PFCl_3, AC % change at T1 (vs. T0) was negatively correlated with semantic fluency (ρ = −0.7939, p = 0.045) and MC % change at T2 (vs. T0) was positively correlated with story memory (ρ = 0.7416, p = 0.045). Conclusions: HF-rTMS stimulation of DLFC nodes significantly affects the controllability of the functional connectome in MCI patients. Emerging correlations between AC/MC controllability and cognitive performance changes, immediately (T1 vs. T0) and six months (T2 vs. T0) after treatment, suggest NCT could help explain the HF-rTMS impact on prefrontal-lateral control network, monitoring induced neural plasticity effects in MCI patients.

Importance: Although whole-body hypothermia is widely used after mild neonatal hypoxic-ischemic encephalopathy (HIE), safety and efficacy have not been evaluated in randomized clinical trials (RCTs), to our knowledge.Objective: To examine the effect of 48 and 72 hours of whole-body hypothermia after mild HIE on cerebral magnetic resonance (MR) biomarkers.Design, Setting, and Participants: This open-label, 3-arm RCT was conducted between October 31, 2019, and April 28, 2023, with masked outcome analysis. Participants were neonates at 6 tertiary neonatal intensive care units in the UK and Italy born at or after 36 weeks’ gestation with severe birth acidosis, requiring continued resuscitation, or with an Apgar score less than 6 at 10 minutes after birth and with evidence of mild HIE on modified Sarnat staging. Statistical analysis was per intention to treat.Interventions: Random allocation to 1 of 3 groups (1:1:1) based on age: neonates younger than 6 hours were randomized to normothermia or 72-hour hypothermia (33.5 °C), and those 6 hours or older and already receiving whole-body hypothermia were randomized to rewarming after 48 or 72 hours of hypothermia.Main Outcomes and Measures: Thalamic N-acetyl aspartate (NAA) concentration (mmol/kg wet weight), assessed by cerebral MR imaging and thalamic spectroscopy between 4 and 7 days after birth using harmonized sequences.Results: Of 225 eligible neonates, 101 were recruited (54 males [53.5%]); 48 (47.5%) were younger than 6 hours and 53 (52.5%) were 6 hours or older at randomization. Mean (SD) gestational age and birth weight were 39.5 (1.1) weeks and 3378 (380) grams in the normothermia group (n = 34), 38.7 (0.5) weeks and 3017 (338) grams in the 48-hour hypothermia group (n = 31), and 39.0 (1.1) weeks and 3293 (252) grams in the 72-hour hypothermia group (n = 36). More neonates in the 48-hour (14 of 31 [45.2%]) and 72-hour (13 of 36 [36.1%]) groups required intubation at birth than in the normothermic group (3 of 34 [8.8%]). Ninety-nine neonates (98.0%) had MR imaging data and 87 (86.1%), NAA data. Injury scores on conventional MR biomarkers were similar across groups. The mean (SD) NAA level in the normothermia group was 10.98 (0.92) mmol/kg wet weight vs 8.36 (1.23) mmol/kg wet weight (mean difference [MD], −2.62 [95% CI, −3.34 to −1.89] mmol/kg wet weight) in the 48-hour and 9.02 (1.79) mmol/kg wet weight (MD, −1.96 [95% CI, −2.66 to −1.26] mmol/kg wet weight) in the 72-hour hypothermia group. Seizures occurred beyond 6 hours after birth in 4 neonates: 1 (2.9%) in the normothermia group, 1 (3.2%) in the 48-hour hypothermia group, and 2 (5.6%) in the 72-hour hypothermia group.Conclusions and Relevance: In this pilot RCT, whole-body hypothermia did not improve cerebral MR biomarkers after mild HIE, although neonates in the hypothermia groups were sicker at baseline. Safety and efficacy of whole-body hypothermia should be evaluated in RCTs.Trial Registration: ClinicalTrials.gov Identifier: NCT03409770

Introduction: Advanced neuroimaging techniques have extensively contributed to elucidate the complex mechanisms underpinning the pathophysiology of migraine, a neurovascular disorder characterized by episodes of headache associated with a constellation of non-pain symptoms. The present manuscript, summarizing the most recent progresses of the arterial spin labelling (ASL) MRI techniques and the most significant findings from ASL studies conducted in migraine, is aimed to clarify how ASL investigations are contributing to the evolving insight on migraine pathophysiology and their putative role in migraine clinical setting. ASL techniques, allowing to quantitatively demonstrate changes in cerebral blood flow (CBF) both during the attacks and in the course of interictal period, could represent the melting point between advanced neuroimaging investigations, conducted with pure scientific purposes, and conventional neuroimaging approaches, employed in the diagnostic decision-making processes.Main body: Converging ASL evidences have demonstrated that abnormal CBF, exceeding the boundaries of a single vascular territory, with biphasic trend dominated by an initial hypoperfusion (during the aura phenomenon but also in the first part of the headache phase) followed by hyperperfusion, characterizes migraine with aura attack and can represent a valuable clinical tool in the differential diagnosis from acute ischemic strokes and epileptic seizures.Studies conducted during migraine without aura attacks are converging to highlight the involvement of dorsolateral pons and hypothalamus in migraine pathophysiology, albeit not able to disentangle their role as “migraine generators” from mere attack epiphenomenon. Furthermore, ASL findings tend to support the presence of perfusion abnormalities in brain regions known to be involved in aura ignition and propagation as well as in areas involved in multisensory processing, in both patients with migraine with aura and migraine without aura.Conclusion: Although ASL studies have dramatically clarified quality and timing of perfusion abnormalities during migraine with aura attacks, the same cannot be said for perfusion changes during migraine attacks without aura and interictal periods. Future studies with more rigorous methodological approaches in terms of study protocol, ASL technique and sample selection and size are mandatory to exploit the possibility of better understanding migraine pathophysiology and identifying neuroimaging biomarkers of each migraine phase in different migraine phenotypes.

Neurodegeneration is a multifactorial process that involves multiple mechanisms. Examples of neurodegenerative diseases are Parkinson’s disease, multiple sclerosis, Alzheimer’s disease, prion diseases such as Creutzfeldt–Jakob’s disease, and amyotrophic lateral sclerosis. These are progressive and irreversible pathologies, characterized by neuron vulnerability, loss of structure or function of neurons, and even neuron demise in the brain, leading to clinical, functional, and cognitive dysfunction and movement disorders. However, iron overload can cause neurodegeneration. Dysregulation of iron metabolism associated with cellular damage and oxidative stress is reported as a common event in several neurodegenerative diseases. Uncontrolled oxidation of membrane fatty acids triggers a programmed cell death involving iron, ROS, and ferroptosis, promoting cell death. In Alzheimer’s disease, the iron content in the brain is significantly increased in vulnerable regions, resulting in a lack of antioxidant defenses and mitochondrial alterations. Iron interacts with glucose metabolism reciprocally. Overall, iron metabolism and accumulation and ferroptosis play a significant role, particularly in the context of diabetes-induced cognitive decline. Iron chelators improve cognitive performance, meaning that brain iron metabolism control reduces neuronal ferroptosis, promising a novel therapeutic approach to cognitive impairment.